Feeding habits and mobility of Equus conversidens and E. mexicanus from La Presita Blanca, State of San Luis Potosi, Mexico

The aim of this study is to determine the feeding habits and home range of fossil horses (Equus conversidens and E. mexicanus) from La Presita Blanca, San Luis Potosi, central Mexico. For this purpose, we used carbon, oxygen, and strontium isotope ratios. We compared Sr-87/Sr-86 from horses with strontium ratios of La Presita Blanca plants and soils to identify if these animals were local or came from elsewhere. The delta C-13 values indicate that E. conversidens specimen consumed C-4 plants and E. mexicanus was a mixed feeder. In this case, carbon isotopic values reflect only the animal's feeding preferences and not the type of vegetation that existed in La Presita Blanca during the Pleistocene. Furthermore, delta O-18 values and strontium isotopic ratios show that E. conversidens was an animal that could be local to the Campo Volcanico de San Luis Potosi whereas E. mexicanus came from another region.